Heat is one of the most sought aftertypes of energy required to maintain human life. At the same time, the cost of resources for its production is quite impressive - whether it is electricity with petroleum products or traditional fuels like coal and wood. Obviously, against this background, there is a need to propose an alternative method of heating. One of the most promising and actively developing technical solutions of this type is the geothermal heat pump, the concept of which is gradually approaching the living conditions of operation.
General information about the technology
Любая идея альтернативного источника тепла involves the maintenance of a natural material or phenomenon. In this case, the central supplier of energy is the subsoil. The soil at certain depths maintains a sufficient temperature so that its heat can be accumulated and subsequently used on the surface. Hydrological resources can also be considered as a source of heat, making their own adjustments to the technical performance of the accumulating infrastructure.
To represent the effectiveness of this technologyIt can be noted that by investing 1 kW of energy in the content of a geothermal heat pump, it is possible to get a return in the form of 2-6 kW. What explains such a high efficiency? Compared to other means of processing natural energy sources, geothermal mechanisms do not provide for intermediate stages of conversion. For example, the accumulation of solar energy requires that light and heat be converted into electricity, which is spent on the maintenance of the house. In this case, the heat is not converted, but directly or with minimal transitional stages is transferred to the target consumers.
Operating principle
For a start, it is worthwhile to identify specific pointswho are involved in the geothermal heating process. The process begins in the ground - at a level that is located below the freezing point. The temperature may vary depending on the depth. For a minimal thermal effect, it is enough that it exceeds 0 ° C, but in practice, 35–40 ° C is considered an economically viable indicator. The end user is the heating circuit.
За перенос энергии от грунта к системе домашнего heating meets a special pipeline, served by a geothermal heat pump. The principle of operation is based on the fact that heat is transferred along this refrigerant circuit through this supply line with a heat exchanger-evaporator. As in air conditioners, freon plays the role of an active evaporated substance. Before the pump starts operation, it is in a liquid state, and after starting it goes into a gaseous form. Next, the updated refrigerant is transferred to the compressor, whose communications are connected to the final heating circuit. Excess freon at this point is discharged through the bypass channel.
Geothermal equipment
The main functional element of the system is a heat pump. The structure of the aggregate is represented by three contours:
- External. It circulates the usual heat carrier in the form of antifreeze or brine.
- Interior. It contains refrigerant in sealed chambers in which heating-evaporation processes take place.
- An external circuit that is directly routed to the target system being served.
Also in the list of working bodies of geothermalThe heat pump for heating includes a compressor, an evaporator, a discharge channel and coolants. It is important to note that the design, layout and additional functionality may vary depending on the conditions of use. There are installations for soil, for water and air, as well as combined systems that can work in different conditions.
Sources of heat and means of storage
Geothermal systems have many advantages associated witheconomical supply of energy, practicality and technological availability for domestic use. But, like other systems that accumulate alternative energy, it is dependent on the source. Therefore, in order to be sure of the stability of heat supply, it is necessary to think in advance about the possibility of connecting to the backup channel of energy supply. Soil and hydrological sources will be discussed below, but for now, you should familiarize yourself with the working infrastructure, which the geothermal heat pump serves as a resource supply system, in principle. Bulk materials, pipes, probes and structures, the structure of which can accumulate energy, act as heat receivers. In particular, it can be heating mats associated with a pump, coolant and third-party heating systems.
Soil heat source
High-performance systems that store geothermal energy are located on fields of about 200 m2. A soil layer is removed from the marked area40-50 cm thick lower than the freezing point. In general, a thickness of 150-200 cm is obtained. These and other data are indicated in the project with the calculation of energy volumes for a particular heating circuit. Much will depend on the region, as in the same area you can extract 30 watts from 1 m2and in the other - 70-80 with 1 m2.
Wells, trenches, orcontinuous platforms for placement of storage elements. The most affordable in the implementation is considered to be a vertical downhole installation, in which spiral accumulating pipes or mats are placed. In the horizontal configuration of the intake infrastructure, a geothermal heat pump for heating can produce large amounts of energy, but it has disadvantages. They relate to the difficulty of excavation (special equipment is required to develop large areas), the exclusion of any landscape work and lowering the temperature by the end of the heating season.
Water source of thermal energy
The main objects of service in this caseprotrude lakes, ponds and ponds. As for the accumulating elements, their function is performed by polymer pipes with antifreeze filling. The volumes of extracted energy on average can be represented as 30 W with 1 m of pipe. For complex maintenance of a large private house, 12 kW is required - accordingly, it is necessary to organize a pipeline system with a length of 400 m.
There is another approach to heat storage fromhydrological resources. If there are no lakes and reservoirs nearby, then on your own site you can equip 2-3 wells with wells with a depth of about 20 m. Water at this level will have a temperature of about 10 ° C, but this is enough for the auxiliary heating function. The bottom line is that a geothermal heat pump performs the task of constantly circulating warm or hot water. On one side of the circuit there is a constant heating of the resource in the wells at no cost, and the energy from the newly received portion of water is accumulated in the house.
Installing a geothermal system
Before making a purchasing decisionequipment, it should be assessed how in a particular region the use of this technology is basically justified. For this, a number of exploration studies are carried out with the determination of the depth of freezing of the soil.
In the installation involved pipes or otheraccumulating elements, pump and installation accessories. Radiators, fan coolers or a warm water floor, etc. can form the internal heating infrastructure. This will be the consumption system of the supplied resource.
So, geothermal thermalpumps for homes in wells - as already noted, not only land, but also water. It is possible to equip wells, trenches and fields with an eliminated layer of soil, but this option is more often used for industrial heat supply. In the created niche, batteries are stacked throughout the site - in a straightforward or spiral configuration. The circuits are connected to a surface-mounted pump, which in turn is connected to home heating circuits.
Geothermal Pump Manufacturers
The segment is actively developing by the efforts of the largestclimate equipment developers. In particular, the manufacturer of boilers Viessmann presents reliable units for water and ground heat storage at an operating temperature of about +65 ° C. For industrial and public buildings with an area of 300-350 m2 NIBE geothermal heat pump availableF1145 Its features include the ability to connect to a three-phase network of 380 V, and a single-phase network of 220 V. Universal from the point of view of the application models of geothermal pumps offers the Japanese company Mitsubishi. Since 2007, the developers of this company have been developing the concept of multi-zone heating separation with a simplified control system.
Do not ignore such a promising segmentand domestic companies. For example, a Russian-made geothermal heat pump BROSK Mark II 100 is designed specifically for a private consumer - the owner of a small country house. But, despite its modest performance, this equipment is characterized as reliable, energy efficient and multifunctional.
Positive feedback on the technology
This method of heating attracts manyease of maintenance, maintenance and, of course, minimal financial costs during operation. The equipment practically does not require fuel consumables. Electric resources are needed to provide the function of the same pump and control equipment, but they are insignificant against the background of the returned amount of energy. Ecological purity of geothermal heat pumps is also emphasized. Reviews do put on one of the first places among the pluses that the working infrastructure does not take up space in the house. Only communications are summed up, and the rest of the functional units and nodes remain on the street.
Negative feedback
With a full heat boilerthe performance of geothermal systems is still not comparable. And the point is not even in specific power indicators, but in spasmodic heat supply. Many complain about long periods of low levels of energy delivery, which is why it is recommended to organize backup supply systems. But here is another flaw. Although a little money is spent on equipment maintenance, the initial investment is comparable to buying a powerful industrial boiler. Even a geothermal heat pump of Russian origin BROSK Mark II 100 is available on the market for 250-300 thousand rubles. depending on the configuration. Installation costs will also cost 50-70 thousand rubles.
Conclusion
Вариантов организации теплоснабжения в условиях There are quite a lot of private houses. Each of them is in its own way costly during operation - from expensive electrical panels to economical gas boilers. But, traditional equipment in a modern design is a system that is optimized in design and easy to manage. What can attract a geothermal heat pump for heating a house? Of course, the economic factor will come to the fore, but what else? You can refer to such installations if the site has enough space for the organization of the complex. In this case, you can count on at least passive auxiliary heating of the premises without constant monitoring and maintenance. And one more thing - this is complete autonomy, allowing you to use geothermal equipment as a backup heat source.
